MAC_SEEOTHERUIDS(4) MidnightBSD Kernel Interfaces Manual MAC_SEEOTHERUIDS(4)


mac_seeotheruids — simple policy controlling whether users see other users


To compile the policy into your kernel, place the following lines in your kernel configuration file:

options MAC

Alternately, to load the module at boot time, place the following line in your kernel configuration file:

options MAC

and in loader.conf(5):



The mac_seeotheruids policy module, when enabled, denies users to see processes or sockets owned by other users.

To enable mac_seeotheruids, set the sysctl OID security.mac.seeotheruids.enabled to 1.

To allow users to see processes and sockets owned by the same primary group, set the sysctl OID security.mac.seeotheruids.primarygroup_enabled to 1.

To allow processes with a specific group ID to be exempt from the policy, set the sysctl OID security.mac.seeotheruids.specificgid_enabled to 1, and security.mac.seeotheruids.specificgid to the group ID to be exempted.

Label Format
No labels are defined for mac_seeotheruids.


mac(4), mac_biba(4), mac_bsdextended(4), mac_ifoff(4), mac_lomac(4), mac_mls(4), mac_none(4), mac_partition(4), mac_portacl(4), mac_test(4), mac(9)


The mac_seeotheruids policy module first appeared in FreeBSD 5.0 and was developed by the TrustedBSD Project.


This software was contributed to the FreeBSD Project by Network Associates Labs, the Security Research Division of Network Associates Inc. under DARPA/SPAWAR contract N66001-01-C-8035 (‘‘CBOSS’’), as part of the DARPA CHATS research program.


See mac(9) concerning appropriateness for production use. The TrustedBSD MAC Framework is considered experimental in FreeBSD.

While the MAC Framework design is intended to support the containment of the root user, not all attack channels are currently protected by entry point checks. As such, MAC Framework policies should not be relied on, in isolation, to protect against a malicious privileged user.

MidnightBSD 0.3 December 8, 2002 MidnightBSD 0.3